1. Field of the Invention
The present invention relates a sheet binding apparatus having means for detecting the presence/absence of a needle, and an image forming apparatus having the binding apparatus. More particularly, it relates to a sheet binding apparatus wherein a stapling operation is effected by the aid of the rotation of a motor and which has means for electrically detecting the presence/absence of a needle.
2. Related Background Art
Conventionally, the presence of a needle or staple in a sheet binding apparatus has been physically detected by a photo-sensor of the permeable type or reflection type. However, in such a conventional technique, since the photo-sensor of permeable type or reflection type was required for detecting the needle, it was difficult to make the sheet binding apparatus small-sized due to the installation space for the photo-sensor and difficult to make the apparatus inexpensive.